• Design & Manufacturing
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• v.2 no.4
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• pp.54-61
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• 2008

Warpage, which is one of the molding trouble, acts as possible factor which results in defect in assembly. In this study, a mold was designed to produce specimens with rib parallel to flow direction, specimens with rib perpendicular to flow direction and specimens without rib. This work researched change of warpage according to injection molding condition such as injection pressure, packing pressure, packing time, resin temperature, mold temperature in non-crystalline resins(PC, ABS), crystalline resins(PP, PA66), and 30% glass fiber reinforced-resins(PC, ABS, PP, PA66).Specimens with rib and Crystalline resins show more warpage than specimens without rib and non-crystalline resins, respectively. Glass fiber reinforced-resins and specimens with rib parallel to flow direction show smaller warpage than conventional resins and specimens with rib perpendicular to flow, respectively. Specimens with rib and specimens without rib show reduced warpage as packing time increases. In addition, warpage increase as resin temperature increases. It is found that CAE shows similar tendency with experiment as packing time, resin temperature. when the rib is caused, warpage will reduce and prevent the transformation. product of a irregular form occurs warpage. In the study It'll be basic data that product occurs warpage, preferablity.

• Journal of Power System Engineering
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• v.3 no.3
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• pp.36-43
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• 1999

Many of thermodynamic-based diesel combustion simulations incorporated a model of fuel spray which attempts to describe how the spray develops according to time. Because the spray geometry is an essential aspect of the fuel-air mixing process, it is necessary to be calculated quantitatively for the purpose of heat release and emission analysis. In this paper, we proposed the calculating method of non-evaporation spray behaviors by injection rate shapes under actual operating conditions of diesel engine. We confirmed the utility of this calculating model as the calculated results were compared with the measured results. This calculating program can be applied usefully to study on the diesel spray behavior.

• Journal of the Semiconductor & Display Technology
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• v.6 no.1 s.18
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• pp.59-64
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• 2007

Non-contact transportation of a large-sized glass plate using air cushion for the vertical sputtering system of liquid crystal display (LCD) panel was considered. The objective of the study was to design an air pad unit which was composed of multiple injection and exhaust holes and mass flow supplying pipe. The gas was injected through multiple small holes to maintain the force for levitating glass plate. After hitting the plate, the air was vented through exhaust holes. Complex flow field and resulting pressure distribution on the glass surface were numerically studied to design the air injection pad. The exhaust hole size was varied to obtain evenly distributed pressure distribution at fixed diameter of the injection hole. Considering the force for levitating glass plate, the diameter of the exhaust hole of 30 to 40 times of the gas injection hole was recommended.

• The Journal of the Korea Contents Association
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• v.15 no.3
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• pp.265-271
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• 2015

This study is the analysis about materials (from 2012 to 2014) which was stored in the data made from the 397 infants subjects who were born in 2012, with the basis of the preventive injection management, public health care information system by using SPSS win 18.0 program. After we analyzed the present non-injection state and the non-injection reasons with the basis of each birth month, each vaccine, each injection period, we found out that 89 infants(22.4%) were the ones who were not computerized. Except the 20 infants-the ones having uncertain phone numbers and addresses, and computerization errors, 69 infants (17.4%) were the ones that didn't get injection. We guided protective injection to them by sending SMS text message and we could inject 39 infants (9.8%) of them. We could achieve the high 92.4% injection rate. we want this research to be used to try wipe out the infectious diseases in this district and be utilized as the basic materials of protective injection cost support and health care policies, etc.

• Archives of Pharmacal Research
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• v.26 no.6
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• pp.493-498
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• 2003

In this study we have investigated the pharmacokinetics and tissue distribution of GX-12, a multiple plasmid DNA vaccine for the treatment of HIV-1 infection. Plasmid DNA was rapidly degraded in blood with a half-life of 1.34 min and was no longer detectable at 90 min after intravenous injection in mice. After intramuscular injection, plasmid DNA concentration in the injection site rapidly declined to less than 1 ％ of the initial concentration by 90 min post-injection. However, sub-picogram levels (per mg tissue) were occasionally detected for several days after injection. The relative proportions of the individual plasm ids of GX-12 remained relatively constant at the injection site until 90 min post-injection. The concentration of plasmid DNA in tissues other than the injection site peaked at 90 min post-injection and decreased to undetectable levels at 8 h post-injection. The rapid in vivo degradation of GX-12 and absence of persistence in non-target tissues suggest that the risk of potential gene-related toxicities by GX-12 administration, such as expression in non-target tissues, insertional mutagenesis and germline transmission, is minimal.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.151.2-151.2
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• 2016

We characterized the n-type organic field-effect transistors (OFETs) with non-conjugated polyelectrolytes (NPEs) interlayers as the electron injection layer. Novel NPEs with various ions (Cl-, Br-, I-) improved the electron mobility from $5.06{\times}10^{-3}$ to $2.10{\times}10^{-2}cm^2V^{-1}s^{-1}$ in OFETs based [6,6]-Phenyl-$C_{61}$-butyric acid methyl ester (PCBM) when $PEIEH^+I^-$ spin-cast from 0.6% solution was deposited onto the PCBM layer. Reduced electron injection barrier (${\phi}_e$) at NPE/metal electrode interface was induced by dipole formation and led to increase the electron injection and transport. These findings are important for understanding how NPEs function in devices, the improvement of device performance, and the design of new materials for use in optoelectronic devices.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.1
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• pp.65-71
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• 2016

Injection rate, injection quantity and injection timing of fuel are controlled precisely by electric control in CRDI system. Particularly, injection rate being influenced with injection pressure affects to spray characteristics and fuel-air ratio, so it is a very important factor in diesel combustion. In this study, injection rates in accordance with injection pressure at a constant ambient pressure were measured with Zeuch's method. Under the same condition, non-evaporating spray images were taken with a high speed camera and analyzed carefully with Adobe Photoshop CS3. Macroscopic spray characteristics and breakup processes in the spray could be found from the examined and analyzed data. Injection start time and injection period were practically affected with injection pressure. Also, initial injection rate, spray penetration, spray angle and breakup of high density droplets region in the spray were affected with injection pressure. The results and techniques of spray visualization and injection rate measurement in this study would be practically effective to study a high pressure diesel spray for common rail direct injection system.

• Journal of ILASS-Korea
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• v.28 no.4
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• pp.169-175
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• 2023

Multi-injection scheme is being applied to GDI combustion to reduce PM and PN emission to meet the EU7 regulation. However, very short injection duration encounters the ballistic injection region, which injection quantity does not increase linearly with injection duration when applying multi-injection. In this study, numerical studies were conducted to reveal the cause of ballistic injection and the effect of design parameters on ballistic region using 1-D simulation, AMESim. Injection rate and injection quantity were compared with experiment to validate the established model, which showed the accuracy with 10% error. The model revealed that the tendency of ballistic region coincides with the needle motion behavior, which means that parameters at the upper part of needle such as electro-magnetic force, needle spring force and needle friction force have dominant effect on ballistic injection. To figure out the effect of electro-magnetic and needle friction force on ballistic, those parameters were varied to plus and minus 10% with model. The result showed that those parameters clearly changed the ballistic region characteristics, however, the impact became insignificant for outside of ballistic region, which means that the ballistic injection is mainly influenced by initial motion of injector needle.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.498-505
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• 2018

This study was aimed to investigate the effects of the type O foot-and-mouse disease vaccine (FMDV) on the incidence of abnormal meat such as granuloma or abscess formation at the injection site in pork and its associated economic losses. At 56 d of age, piglets were inoculated with FMDV by one of three administration routes: N-Neck (a conventional needle-syringe injection into the neck), N-Ham (a conventional needle-syringe injection into the ham), and Non-Neck (injection with a needle-free device into the neck). The injection sites were visually examined for the presence of a granuloma or abscess, and the incidence rate of abnormal meat was calculated. The gross weight of the portion of the pork carcasses condemned because of granuloma or abscess formation was measured and multiplied by the weekly sales price to calculate the total economic losses. After implementation of FMDV, the economic losses were approximately six times higher than before implementation. Granuloma or abscess formation was significantly higher in the N-Neck and Non-Neck groups, in which the vaccine was inoculated into the neck area, than in the N-Ham group (N-Neck and N-Ham vs Non-Neck, p<0.05). These results suggest that the incidence of lesions could be reduced if the ham route was used for vaccination.

• Journal of Dental Anesthesia and Pain Medicine
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• v.22 no.5
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• pp.387-394
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• 2022

Background: Dental pain management is an important aspect of patient management in pediatric dentistry. Articaine is considered the most successful anesthetic agent for infiltration anesthesia. Buffered articaine has been observed to have faster onset and longer duration of action with less pain on injection. The aim of this study was to evaluate and compare pain on injection, onset of action, and pain during extraction using buffered (using Sodium bicarbonate (NaHCO₃)) and non-buffered 4% articaine (with 1:100000 adrenaline) infiltrations for primary maxillary molar extractions in 4-10-year-old children. Methods: Seventy children who required extraction of maxillary primary molars were enrolled in this triple-blind randomized study. Children undergoing extraction were randomly divided into two groups, with 35 in each group. The study group was the buffered articaine group; the control group was the non-buffered articaine group. Buccal and palatal infiltrations were administered with either buffered or non-buffered articaine. Subjective evaluation was done for pain on injection, pain during extraction using Wong-Baker Faces Pain Rating Scale (WBFPR) and onset of anesthesia in seconds. Pain on injection, pain during extraction were objectively evaluated using Sound Eye Motor (SEM) scale and onset of anesthesia was also evaluated objectively by pricking with sharp dental probe. Results: The outcome was, significantly less pain on injection and significantly faster onset of anesthesia with significantly less pain during extraction for both subjective and objective evaluations in the buffered articaine group. Subgroup analysis was also performed and it showed variable results, with only significant difference for WBFPR scores in age subgroup 4-7 years for palatal infiltration. Conclusion: Less pain on injection, faster onset of anesthesia, and less pain during extraction were observed when buffered articaine was used for maxillary primary molar extraction.